ESO to produce ALMA antennae

The largest European industrial ground-based astronomy contract will allow ALMA to study cool gas and dust, the remnants of the Big Bang.
By | Published: January 4, 2006 | Last updated on May 18, 2023
ALMA plans
The Atacama Large Millimeter Array (ALMA) in Chile will have a collecting area of more than 60,000 square feet when it’s complete. The giant array is expected to start partial operations by 2011.
January 4, 2006
The European Organisation for Astronomical Research in the Southern Hemisphere (ESO) is set to supply 25 custom-constructed antennae to the Atacama Large Millimeter Array (ALMA), located at a 16,400-foot-high (5,000 meters) site in Chile’s Atacama Desert.

ALMA is a juggernaut of an instrument. It’s the world’s most sensitive astronomical instrument at millimeter and submillimeter wavelengths — radio waves through infrared radiation. Its sensitivity will be 20 times that of the Very Large Array (VLA) in Socorro, New Mexico. This unsurpassed level of sensitivity will allow ALMA to produce precise images at an angular resolution of 0.1″ as well as additional images at a jaw-dropping 0.01″ resolution.

ALMA prototype
ALMA’s antennae will each measure 39 feet across and be separated by baselines of up to 11 miles. This prototype is being tested at the Very Large Array (VLA) site in Socorro, New Mexico.
With its new antennae, ALMA will target molecular gas and dust in protoplanetary disks that surround Sun-like stars in the Milky Way and nearby galaxies. Capable of imaging these star-forming regions at a distance of 489.25 light-years, ALMA will be able to detect the chemical compositions, physical makeup, and magnetic-field structures within these planet-forming disks.

One goal of this project is to use ALMA’s impressive resolution to study the gravitational collapse of dense molecular gas and dust clouds in order to reveal the detailed mechanics of star formation.

The $176 million (147 million Euros) contract, signed December 6, 2005, at the ESO’s Garching, Germany, headquarters, includes the antennae’s design, manufacture, transport, and on-site integration. The ESO has already built a prototype antenna that has been tested extensively at the ALMA Antenna Test Facility at the VLA site in Socorro, New Mexico.

ALMA is an international partnership between North America, Europe, and Japan, in cooperation with the Republic of Chile.